Even more, like different people and races have different languages, different bacteria use different chemical 'words'. Broadly classifying, the gram negative bacteria use small molecules like acyl homocerine lactones (AHLs) and the gram positive bacteria use peptides.
Initially it was believed that these words are species specific but later research revealed that there are infact more viz., intra species, inter species and also the ones which are commonly spoken by most of all bacteria. I would love to decode their language as the following; the intra species i.e., to recognize the cells of its own kind they say, 'me' and for the ones which are of different species but the same genus, like their ‘cousins’, they say 'you' and for the others, 'we'; in v.fischeri the molecules are called AI-1, CAI-1 and AI-2 respectively. They are chemically
different from one another and the ‘AI-2’ is spoken by most known bacteria.
It was my turn to present an article in the journal club here in our department this week. This time, I choose to talk about 'quorum sensing'; the name in "our" language to address their (bacterial) language. Isn't that an interesting topic to talk about? after-all, all we are fond of gossips and in this case the ‘bacterial gossips’!
It was an 2009 article in ‘PloS biology’ journal from Bonnie L. Bassler's group who at the first place reported the quorum sensing in the bacteria, vibrio fischeri. It was an amazing experience to learn and share about this incredible system of these tiny little single celled bugs. This particular article is about vibrio harveyi and would like to write here a few things I learnt over reading the article (over a late working night, in fact(! ).
Facinating, isn't it??!! But, that not all about it. We only know very little and they have lot more secrets to be revealed.
Still, with the least known, we have developed counter-technology to trick them not to do something unfavourable for us. Its been shown by scientists that by sending some similar but wrong chemical words, the bacteria never know their troops are ready to attack and they stay calm, in the case of pathogenesis. In the field of medicine, the topic now is about the growing ristk of antibacterial resistance among the bacterial pathogens, yet another facinating thing these guys are doing. But this invention has opened a new way of fighting bacterial infections, the next generation antibiotics, so to say. So, thanks to those scientists and PhD students (:O)) who made those discoveries.
Let us wish, the current global economic melt down dont stop them from doing much more!